Anti-ulcerogenic activity of aqueous extract of Carica papaya seed on indomethacin-induced peptic ulcer in male albino rats

OBJECTIVE: Carica papaya is an important fruit with its seeds used in the treatment of ulcer in Nigeria. This study investigated the anti-ulcerogenic and antioxidant activities of aqueous extract of Carica papaya seed against indomethacin-induced peptic ulcer in male rats.METHODS: Thirty male rats were separated into 6 groups(A–F) of five rats each. For 14 d before ulcer induction with indomethacin, groups received once daily oral doses of vehicle(distilled water), cimetidine 200 mg/kg body weight(BW), or aqueous extract of C. papaya seed at doses of 100, 150 or 200 mg/kg BW(groups A, B, C, D, E and F, respectively). Twenty-four hours after the last treatment, groups B, C, D, E and F were treated with 100 mg/kg BW of indomethacin to induce ulcer formation. RESULTS: Carica papaya seed extract significantly(P<0.05) increased gastric p H and percentage of ulcer inhibition relative to indomethacin-induced ulcer rats. The extract significantly(P<0.05) decreased gastric acidity, gastric acid output, gastric pepsin secretion, ulcer index and gastric secretion volume relative to group B. These results were similar to that achieved by pretreatment with cimetidine. Specific activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase in the extract-treated groups(D, E and F) were increased significantly over the group B(P<0.05). Pretreatment with the seed extract protected rats from the indomethacin-mediated decrease in enzyme function experienced by the group B. Similarly, indomethacin-mediated decrease in reduced glutathione level and indomethacin-mediated increase in malondialdehyde were reversed by Carica papaya extract. CONCLUSION: In this study, pretreatment with aqueous extract of Carica papaya seed exhibited antiulcerogenic and antioxidant effects, which may be due to the enhanced antioxidant enzymes.     

Clinical Validation and Implementation of a Targeted Next-Generation Sequencing Assay to Detect Somatic Variants in Non-Small Cell Lung,Melanoma, and Gastrointestinal Malignancies

We tested and clinically validated a targeted next-generation sequencing (NGS) mutation panel using 80 formalin-fixed, paraffin-embedded (FFPE) tumor samples. Forty non-small cell lung carcinoma (NSCLC), 30 melanoma, and 30 gastrointestinal (12 colonic, 10 gastric, and 8 pancreatic adenocarcinoma) FFPE samples were selected from laboratory archives. After appropriate specimen and nucleic acid quality control, 80 NGS libraries were prepared using the Illumina TruSight tumor (TST) kit and sequenced on the Illumina MiSeq. Sequence alignment, variant calling, and sequencing quality control were performed using vendor software and laboratory-developed analysis workflows. TST generated ≥500× coverage for 98.4% of the 13,952 targeted bases. Reproducible and accurate variant calling was achieved at ≥5% variant allele frequency with 8 to 12 multiplexed samples per MiSeq flow cell. TST detected 112 variants overall, and confirmed all known single-nucleotide variants (n = 27), deletions (n = 5), insertions (n = 3), and multinucleotide variants (n = 3). TST detected at least one variant in 85.0% (68/80), and two or more variants in 36.2% (29/80), of samples. TP53 was the most frequently mutated gene in NSCLC (13 variants; 13/32 samples), gastrointestinal malignancies (15 variants; 13/25 samples), and overall (30 variants; 28/80 samples). BRAF mutations were most common in melanoma (nine variants; 9/23 samples). Clinically relevant NGS data can be obtained from routine clinical FFPE solid tumor specimens using TST, benchtop instruments, and vendor-supplied bioinformatics pipelines.In modern oncologic practice, patients with advanced-stage non-small cell lung cancer (NSCLC),^{1, 2} melanoma,^{3, 4} and colorectal adenocarcinoma^{5, 6} are often treated with targeted therapies as standard of care or after enrollment in clinical trials. Molecular mutation analysis is the preferred testing modality to guide therapeutic decision making and/or eligibility for biological studies. Therefore, laboratory-developed mutation assays require robust workflows that produce high-quality sequence information from routine clinical specimens, namely formalin-fixed, paraffin-embedded (FFPE) samples. As molecular testing transitions from an ancillary tool to a seminal requirement for optimal oncologic patient management, multiplex sequencing assays with clearly defined content and bioinformatics workflows are essential for accurate and consistent results, reporting, and patient management.Published guidelines endorse which genes to test in a particular tumor type and provide timeframes for receipt of actionable results, but they also grant individual laboratories autonomy to perform mutation testing using any suitable validated method.² Historically at our institution, single-gene mutation analysis for clinically relevant genes was performed either in-house or at a Clinical Laboratory improvement Amendment–certified reference laboratory. Depending on the result, reflex testing was performed for additional genes per mutation frequency or designated algorithms. Unfortunately, this approach introduced considerable turn-around time delays and unnecessary cost, particularly when send-out testing was required. Therefore, we sought testing modalities that could analyze multiple clinically relevant mutations simultaneously, accurately, and expeditiously.Next-generation sequencing (NGS) technologies have revolutionized genomic medicine by allowing high-throughput, parallel sequencing of the human genome.⁷ Currently, however, a large proportion of clinical NGS endeavors are supported by larger academic institutions with shared access to established genomic and bioinformatics research infrastructures, and routine clinical implementation of NGS is complicated by mitigating factors, such as clinical performance, laboratory expertise, lengthy turn-around times, and cost.⁸ Thus, we investigated affordable methods to detect clinically relevant somatic mutations in NSCLC, melanoma, and gastrointestinal (GI) malignancies that generated high-quality sequencing data from FFPE samples, and offered manageable turn-around times. Targeted amplicon-based library preparation methods combined with parallel sequencing offered a practical solution, and recent studies have demonstrated the utility of this approach.^{9, 10}Reversible terminal dideoxynucleotide sequencing chemistry by Illumina (San Diego, CA) consistently generates accurate and reproducible sequencing data.^{11, 12} To use this chemistry for clinical testing, we purchased the bench-top NGS sequencer, the Illumina MiSeq, and paired it with the MiSeq-compatible Illumina TruSight tumor (TST) 26-target amplicon-based library preparation kit. TST targets 26 genes and 174 amplicons selected from College of American Pathologists/National Comprehensive Cancer Network guidelines, relevant publications, and late-phase pharmaceutical clinical trials (Supplemental Table S1). TST offered several advantages over other commercially available mutation testing kits, such as bidirectional targeting of the positive and negative DNA strands, full-exon coverage as opposed to hotspot analysis, and robust vendor-supplied bioinformatics techniques optimized for somatic variant detection. More important, TST library preparation is optimized for FFPE samples, multiple safeguards exist to detect FFPE variant artifacts, and deep sequencing of TST libraries consistently yields high depths of coverage of targeted regions.Somatic mutation testing for many of the TST genes has clinical utility in a wide variety of solid tumors. For example, testing for CTNNB1 exon 3 is performed clinically for diagnostic and prognostic purposes in pediatric desmoid tumors, select PIK3CA hotspot mutations are positive prognostic factors for breast carcinoma, and multiple exons in PDGFRA and KIT are routinely tested in GI stromal tumors to predict response to targeted therapies. More important for our intended validation purposes, all of the clinically relevant genes and regions mutated in NSCLC, melanoma, and colonic adenocarcinoma that were tested in our routine clinical practice were represented. In addition, we could easily incorporate the TST NGS into a 5 business day workflow model, and a cost-analysis demonstrated a reasonable cost per test.Last, TST NGS data are processed from raw sequence (FASTQ) to called variants with on-board MiSeq Reporter software version 2.3, and variant annotations can be performed with Illumina''s VariantStudio software version 2.1 software using standard desktop and laptop computers. The ease of library preparation, sequencing, and data analysis with tools provided by a single vendor best fit our clinical priorities and the resources available at our academic molecular pathology laboratory.Herein, we present our results from the clinical validation of TST NGS using 80 sequenced samples that were selected from 100 FFPE patient samples (40 NSCLCs, 30 melanomas, and 30 GI malignancies). During our validation, we achieved high depths of coverage for multiple clinically relevant variants when multiplexing 8 to 12 samples on a single MiSeq flow cell. TST NGS consistently demonstrated sensitivities comparable to reference assays, showed 100% concordance with known variants, detected novel variants in many samples, and uncovered variants missed by less-sensitive testing modalities. The TST variant-calling pipeline was robust and showed high concordance when compared with an alternative analysis pipeline, and we used an in-house custom Java program to assess laboratory-defined quality control (QC) metrics and streamline clinical reporting (developed by G.H.S., Emory University, http://github.com/ghsmith/coverageQc). More important, although the results detailed herein represent the experience of a single institution, the data and validation strategies shown herein are broadly applicable to most clinical molecular laboratories interested in offering NGS for NSCLCs, melanomas, and GI malignancies as well as many other solid tumors.     

NNK promotes migration and invasion of lung cancer cells through activation of c-Src/PKCι/FAK loop

Cigarette smoking, either active or passive, is the most important risk factor in the development of human lung cancer. Mounting evidence indicates that cigarette smoke constituents not only contribute to tumorigenesis but also may increase the spread of cancer in the body. Nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is formed by nitrosation of nicotine and has been identified as the most potent carcinogen. NNK, an important component in cigarette smoke, may also promote tumor metastasis by regulating cell motility. Here we found that NNK can induce activation of a functionally interdependent protein kinase cascade, including c-Src, PKCι and FAK, in association with increased migration and invasion of human lung cancer cells. c-Src, PKCι and FAK are extensively co-localized in the cytoplasm. Treatment of cells with α₇ nAChR specific inhibitor α-bungarotoxin (α-BTX) blocks NNK-stimulated activation of c-Src, PKCι and FAK and suppresses cell migration and invasion. Intriguingly, NNK enhances c-Src/PKCι and PKCι/FAK bindings, indicating a potential mechanism by which these kinases activate each other. Specific disruption of c-Src, PKCι or FAK expression by RNA interference significantly reduces NNK-induced cell migration and invasion. These findings suggest that NNK-induced migration and invasion may occur in a mechanism through activation of a c-Src/PKCι/FAK loop, which can contribute to metastasis and/or development of human lung cancer.